Average answer time for chat messages

Hi selinozdemirpbi ,

Please have a try.

Measure =
VAR _a =
    SUMMARIZE (
        'Table',
        'Table'[sender_id],
        'Table'[receiver_id],
        "Time",
            DATEDIFF (
                MAXX (
                    FILTER (
                        ALL ( 'Table' ),
                        [sender_id] = EARLIER ( 'Table'[receiver_id] )
                            && [receiver_id] = EARLIER ( 'Table'[sender_id] )
                            && [spesific_group] = "No"
                    ),
                    [date-hour]
                ),
                MAX ( 'Table'[date-hour] ),
                MINUTE
            )
    )
RETURN
    AVERAGEX ( _a, [Time] )

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